https://en.wikipedia.org/w/index.php?title=Smallpox_in_Australia&diff=prev&oldid=1168466980
What happens?:
I replaced a footnote which was duplicating another footnote by:

1. pressing one of them
2. Pressing Convert
3. Press "Back" after it has finished loading the "automatic" filling
4. Press "re-use"
5. Find the other footnote which I wanted to group.
6. Press "Use".
7. Save page

This caused VE to name the footnotes :0, but that name was already used by another reference.
"Cite error: The named reference ":0" was defined multiple times with different content"

What should have happened instead?:

It should have used another name for the references, such as :1